Best Management Practices

The Great Salt Plains Lake is one of Oklahoma's most unique areas.  The Great Salt Plains Lake is located just west of Cherokee Oklahoma. On the shores of the lake lie 11,000 acres of salt plains. The lake is part of the Salt Plains National Wildlife Refuge. The salt plains and lake are a seasonal home to many migratory birds. The area is an important stopping place for ducks and geese during their trip over the plains.

The salt plains are thought to be a remnant ocean flooding millions of years ago. These plains are the only place in the world where hourglass shaped Selenite crystals can be found. Selenite crystal is a form of gypsum. They grow just below the salt encrusted surface. The crystals grow and dissolve with the changes in salinity of the brine that lies under the surface of the salt plains.

The lake averages only 4 feet deep. The lake water is about half as salty as ocean water. In recent years siltation has become an increasing problem for the lake and its tributaries. Pesticides and nutrients from the wheat fields of Oklahoma and Kansas wash into tributaries that feed the reservoir. Excessive nutrients cause algae blooms that deplete the water of oxygen and kill fish.

The purpose of this project is to demonstrate how changes in the management practices of agricultural lands in the watershed affect the lake. Computer modeling is used to make predictions. This web page focuses on the computer modeling aspect of the project. Soil and Water Assessment Tool (SWAT) is the model that will be used to predict the amount of nutrients that reach the lake. Excessive nutrients can affect the lake and surrounding ecosystem. More information regarding the S.W.A.T. model can be found at the USDA-ARS_Grassland Soil and Water Research Laboratory.

 Location

The watershed covers some 8,000 square kilometers around the Oklahoma-Kansas border. Much of this area is used for farming and grazing cattle. Because the watershed is on the border, there are few data sets that include the entire watershed. Much of the data is pieced together from two or more different sources.

Coming Soon Pictures in the Salt Fork Watershed.

A growing collection of lab assignments and data used to teach SWAT.

NEW Go to SWAT Educational Materials

A collection of macros used to speed up the modeling process.

NEW Go to the ArcView SWAT tools page

Soil data is an important part of the model. This particular area required 3 different coverages be combined to cover the area.

 Go to the soil data information page

 The final land cover data is not yet available, however trial model runs are using data that is available.

Go to the land cover data page

 Elevation Data

Elevation is determined from USGS DEMs. Over 90 - 1:24,000 scale DEMs were used to complete the elevation grid.

Go to the Elevation data page

Questions or comments contact,

Site Maintainer: Mike White